SNAPCARD API Example

Snapcard.cs

using System;
using System.IO;
using System.Net;
using System.Security.Cryptography;
using System.Text;

namespace apitest1
{
	class MainClass
	{
		public static void Main(string[] args)
		{
			SnapcardApi snapcardApi = new SnapcardApi();

			string balance = snapcardApi.getMerchantBalance();
			Console.WriteLine(balance);

			string invoiceData = "{ \"fiatAmount\":1, \"fiatType\":\"USD\", \"order\":\"4817123124\", \"customer\":\"testCustomer\" }";
			string createdInvoice = snapcardApi.createInvoice(invoiceData);
			Console.WriteLine(createdInvoice);
		}
	}

	public class SnapcardApi {
		private const string domain = "https://www.snapcard.io";
		private const string apiKey = "9vpiv3noekf2uk8nr1f3pekoi6hf3kll";
		private const string secKey = "l512t1lmf1pnse5jnv2f75n5gd59n2to";

		public string getMerchantBalance() 
		{
			return MakeGetReq("/api/v1/merchant/balance");
		}

		public string createInvoice(string jsonString)
		{
			return MakePostReq("/api/v1/invoice/create", jsonString);
		}

		private string MakeGetReq(string apiRoute)
		{
			WebRequest req = AssembleWebRequest(apiRoute);
			req.Method = "GET";
			WebResponse response = req.GetResponse();
			string responseString = ParseWebResponse(response);
			return responseString;
		}

		private string MakePostReq(string apiRoute, string jsonData)
		{
			WebRequest req = AssembleWebRequest(apiRoute, jsonData);
			req.Method = "POST";
			WriteJsonToRequest(req, jsonData);


			WebResponse response = req.GetResponse();
			string responseString = ParseWebResponse(response);
			return responseString;
		}

		private WebRequest AssembleWebRequest(string apiRoute, string jsonData = "")
		{
			string url = domain + apiRoute + "?EXPIRATION=" + GetExpirationTime();
			WebRequest request = WebRequest.Create(url);
			request.ContentType = "application/json";
			request.Headers["AUTH_API_KEY"] = apiKey;
			string authSig = CalcAuthSigHash(secKey, url + jsonData);
			request.Headers["AUTH_SIG"] = authSig;
			return request;
		}

		private void WriteJsonToRequest(WebRequest req, string jsonData)
		{
			var streamWriter = new StreamWriter(req.GetRequestStream ());
			streamWriter.Write(jsonData);
			streamWriter.Close();
		}

		private string GetExpirationTime()
		{
			return DateTime.Now.AddMinutes(5).ToString();
		}

		private byte[] GetBytes(string str)
		{
			return Encoding.UTF8.GetBytes(str);
		}

		private string GetString(byte[] bytes)
		{
			return BitConverter.ToString(bytes);
		}

		private string CalcAuthSigHash(string key, string value)
		{
			HMACSHA256 hmac = new HMACSHA256(GetBytes(key));
			string hash = GetString(hmac.ComputeHash(GetBytes(value)));
			hash = hash.Replace("-", "");
			return hash;
		}

		private string ParseWebResponse(WebResponse response)
		{
			StreamReader streamReader = new StreamReader(response.GetResponseStream());
			string result = streamReader.ReadToEnd();
			streamReader.Close();
			return result;
		}
	}
}